I first read Tocqueville almost fifty years ago, as part of my French studies at the university. As I was largely ignorant of social science and of history, I was unable to benefit from him. When I returned to Democracy in America fifteen years later, having spent most of the intervening years learning those disciplines, I had an experience I have only had with two other books, Thomas Schelling's Strategy of Conflict and Paul Veyne's Le pain et le cirque. The work put me in such a state of intellectual and nervous excitement that I could not sit still, but had to get up from my chair and walk about from time to time.

When I tried to penetrate more fully into the work, its brilliance began to seem more blinding than illuminating. As I explain in the Introduction and document throughout the book, Tocqueville's unsystematic, not to say incoherent, analyses detract from the value of Democracy in America as a guide to either democracy or America. On further reflection, however, I was able to understand why my initial impression was justified. Instead of assuming that Tocqueville was a political theorist or an observer of American society, I began reading him as a social scientist. Democracy in America is filled to the brim – indeed, sometimes overflowing – with small and medium-sized causal mechanisms and highly sophisticated methodological insights that, although they do not add up to the grand theory to which he aspired, have lasting value.